EP0115747A1 - Electronic antitheft device comprising an electronic key - Google Patents

Electronic antitheft device comprising an electronic key Download PDF

Info

Publication number
EP0115747A1
EP0115747A1 EP83830002A EP83830002A EP0115747A1 EP 0115747 A1 EP0115747 A1 EP 0115747A1 EP 83830002 A EP83830002 A EP 83830002A EP 83830002 A EP83830002 A EP 83830002A EP 0115747 A1 EP0115747 A1 EP 0115747A1
Authority
EP
European Patent Office
Prior art keywords
circuit
inductance
signal
electronic key
receiver part
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP83830002A
Other languages
German (de)
French (fr)
Inventor
Pietro Crosetto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SAET SpA
Original Assignee
SAET SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SAET SpA filed Critical SAET SpA
Priority to EP83830002A priority Critical patent/EP0115747A1/en
Publication of EP0115747A1 publication Critical patent/EP0115747A1/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/00174—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
    • G07C9/00309—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated with bidirectional data transmission between data carrier and locks
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/00174—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
    • G07C2009/00753—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys
    • G07C2009/00769—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys with data transmission performed by wireless means
    • G07C2009/00777—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys with data transmission performed by wireless means by induction

Definitions

  • the subject of the present invention is an electronic anti-theft device comprising an electronic key which can be engaged with a fixed receiver part having the function of carrying out a process of identification of the electronic key engaged therewith and of providing an enabling signal to actuator means when the electronic key engaged with the receiver part has predetermined characteristics.
  • Anti-theft devices of the said type generally include electronic keys in each of which there are incorporated electrical or electronic circuits, of the analogue or digital type, connected to electrical contacts fixed to the outer surface of the electronic key.
  • the fixed receiver part is similarly provided with electrical contacts which are accessible from the outside and are intended to couple with the contacts of the key when the latter is inserted in the receiver part to achieve the electrical connection of the internal circuits of the key with the internal circuits of the receiver part.
  • the internal circuit of the electronic key may also be constituted solely by one or more resistors having a calibrated resistance value or may include more complex circuits such as for example memory circuits, shift registers, etc.
  • the devices of the types noted above have a problem due to the fact that their correct operation depends in a decisive manner on the state of the electrical contacts of the key and of the receiver part. In effect, even a single partially oxidised or dirty contact can cause lack of recognition of the correct electronic key.
  • the problem displayed by the said electrical contacts has a further aspect.
  • the receiver part of an anti-theft device is usually installed in a place accessible to the public, for example close to an access door to an environment of which it is desired to allow the.opening only to the possessors of a particular electronic key. This gives rise to a real danger from acts of vandals who might damage the electrical contacts of the receiver part, thus making the identification of the electronic keys subsequently coupled to this receiver part impossible.
  • the object of the present invention is to provide an electronic anti-theft device of the electronic key type which does not have the disadvantages of the prior art devices and in which both the electronic key and the receiver part do not require electrical contacts which are accessible from outside for operation of the device.
  • the present invention provides an electronic anti-theft device of the type specified above, the main characteristic of which lies in the fact that the receiver part comprises:
  • the electronic anti-theft device includes an electronic key 1 which can be engaged with a receiver part 2 fixed, for example, to a wall 3 close to a door for access to an environment (not shown).
  • the receiver part 2 includes an oscillator 4 connected to a resonant circuit of the LC-series type including a capacitor 5 and an inductance 6.
  • 7 shows an amplitude demodulating circuit having its input connected to the common terminal of the inductance 6 and the capacitor 5.
  • the output of the demodulating circuit 7 is connected to a comparator and recognition circuit 8 the output of which is connected to actuator means (not shown) constituted,for example,by devices for opening a lock or devices which control the operation of optical and/or acoustical type alarms.
  • the electronic key 1 includes a second inductance 9 intended to be coupled magnetically to the inductance 6 of the receiver part 2 when the electronic key 1 is engaged with the receiver part.
  • the receiver part 2 includes a support body 2a having afrontally open recess 2b for receiving a complementary shaped projection 1a which extends from an end face of the electronic key 1.
  • Within the projection 1a of the electronic key 1 is located the winding of the inductance 9 which is also constituted by an annular coil.
  • the projection 1a of the key engages the recess 2b of this receiver part and the inductance winding 9 is located concentrically within the inductance winding 6.
  • the magnetic field generated by the current circulating in the inductance 6 is, in this situation, coupled to the inductance winding 9 of the electronic key 1.
  • a transistor 10, of the NPN type has its emitter connected to one end of the inductance winding 9 and its collector connected to the other end of this winding through a resistor 11.
  • This resistor has a rather low resistance value.
  • the point of connection of the inductance winding 9 to the resistor 11 is connected to the anode of a rectifier diode 12, the cathode of which is connected to the input of a stabilized supply 13.
  • a capacitor 14 is connected between the cathode of the diode 12 and earth.
  • AA coded-binary signal generator circuit 15 has its output connecte o the base of the transistor 10 through a resistor 16 and an inverter 15a.
  • the coded-signal generator circuit 15 is arranged to output an information signal of the type illustrated by way of example in Figure 3.
  • This signal includes successive signal portions of equal duration T with each of which is associated an information bit.
  • Each of these signal portions may assume a first or a second waveform according to whether the information bit associated therewith corresponds to a logic "0" or a logic "1".
  • the waveform associated with "0" is preferably constituted by a pulse of duration T having a constant amplitude V 0 .
  • the waveform associated with "1" is constituted by a pulse of duration ⁇ T, having a constant amplitude V o followed or preceded by an interval of duration T - ⁇ in which the signal has substantially zero anplitude.
  • Figure 3 shows a portion of signal associated with the sequence "....010.".
  • the waveform 3 associated with the "0" and the "1" may obviously be interchanged.
  • the oscillator 4 is arranged,in a manner known per se to generate a signal having a predetermined frequency wnich is independent of the variations in the load impedance of the oscillator.
  • the resonant frequency of the resonant circuit comprising the capacitor 5 and the inductance 6, under the conditions in which the electronic key is not engaged with the receiver part is the same as the frequency of the oscillator 4.
  • This frequency may for example, be 100 KHz.
  • the amplitude of the voltage across the inductance 6 remains constant. Consequently the output signal of the demodulator circuit 7 is a continuous signal, which,under these conditions, has a constant amplitude.
  • This coded signal is passed through the inverter 15a to the transistor base 10. Consequently when the coded signal has an amplitude V 0 the transistor 10 is cut off. When the coded signal has a substantially zero amplitude the transistor 10 is saturated. At each change from the condition of saturation to the condition of cut-off of the transistor 10 there is a corresponding variation which can be sensed by the inductive component of the impedance of the resonant circuit in the receiver part 2. The resonant frequency of this circuit, and consequently the amplitude of the voltage across the inductance 6 varies correspondingly. In other words, the coded signal emitted by the generator circuit 15 acts as a signal modulating the amplitude of the voltage across the inductance 6.
  • the amplitude demodulator 7 outputs a unidirectional signal the sequential progress of which follows the variations in the sequential progress of the modulating signal, that is, the signal putput of the generator circuit 15.
  • the signal output of the demodulating circuit 7 is compared by the comparator and recognition circuit 8 with a predetermined reference sequence. When these coincide, the .electronic key 1 coupled to the receiver part 2 is "recognised” and the comparator and recognition circuit 8 outputs an enabling signal to actuator means of the type mentioned above, or prevents the actuation of alarm means. In the case of lack of recognition of the key, the comparator and recognition circuit 8 activates the alarm means or inhibits the actuation of the actuator means mentioned above.
  • the inductance 9 When the signal output of the generator circuit 15 causes saturation of the transistor 10 the inductance 9 is substantially short-circuited. In this situation it is necessary that the short-circuiting of the inductance 9 does not last for an excessively long time, in order to avoid reduction of the supply of the coded-signal generator circuit 15.
  • the coded signal ouput of the generator circuit 15 must not remain at the low level beyond a fraction of the duration T of an individual portion of the coded signal.
  • the above-mentioned characteristic of the coded signal output of the generator circuit 15 lies in the fact that this coded signal has an average v lue which is not zero in any time interval of duration T, ensuring the continuity of the supply to the coded signal generator circuit 15 when the key 1 is inserted in the receiver part 2.
  • the electronic key anti-theft device has the advantage of not requiring the use of fixed contacts for the key and the receiver part and thus is free of all the disadvantges which result from the presence of such contacts.

Abstract

@ The device includes an electronic key (1) which can be engaged with a fixed receiver part (2) which has the function of carrying out a process of identification of the electronic key (1) engaged therewith. The receiver part (2) includes an oscillator (4) connected to a resonant circuit (5, 6) including an inductance (6), and a detector circuit (7) arranged to provide an electrical signal indicative of variations in the characteristics of the voltage across this inductance (6). A comparator circuit (8) is connected to the detector circuit (7) and outputs an enabling signal when the sequential combination of the signal output of the detector circuit (7) coincides with a predetermined sequential combination.
The electronic key (1) includes a second inductance (9) which can be coupled magnetically to the first inductance (6) to couple the electronic key (1) to the receiver part (2) and an electronic control circuit (10-16) connected to the second inductance (9) and adapted to vary statically the degree of magnetic coupling between the first and second inductances (6, 9) in a predetermined manner when the electronic key (1) is engaged with the receiver part (2), so as to cause corresponding variations in the characteristics of the voltage across the first inductance (6).

Description

  • The subject of the present invention is an electronic anti-theft device comprising an electronic key which can be engaged with a fixed receiver part having the function of carrying out a process of identification of the electronic key engaged therewith and of providing an enabling signal to actuator means when the electronic key engaged with the receiver part has predetermined characteristics.
  • Anti-theft devices of the said type generally include electronic keys in each of which there are incorporated electrical or electronic circuits, of the analogue or digital type, connected to electrical contacts fixed to the outer surface of the electronic key. The fixed receiver part is similarly provided with electrical contacts which are accessible from the outside and are intended to couple with the contacts of the key when the latter is inserted in the receiver part to achieve the electrical connection of the internal circuits of the key with the internal circuits of the receiver part.
  • The internal circuit of the electronic key may also be constituted solely by one or more resistors having a calibrated resistance value or may include more complex circuits such as for example memory circuits, shift registers, etc.
  • The devices of the types noted above have a problem due to the fact that their correct operation depends in a decisive manner on the state of the electrical contacts of the key and of the receiver part. In effect, even a single partially oxidised or dirty contact can cause lack of recognition of the correct electronic key.
  • The problem displayed by the said electrical contacts has a further aspect. The receiver part of an anti-theft device is usually installed in a place accessible to the public, for example close to an access door to an environment of which it is desired to allow the.opening only to the possessors of a particular electronic key. This gives rise to a real danger from acts of vandals who might damage the electrical contacts of the receiver part, thus making the identification of the electronic keys subsequently coupled to this receiver part impossible.
  • The object of the present invention is to provide an electronic anti-theft device of the electronic key type which does not have the disadvantages of the prior art devices and in which both the electronic key and the receiver part do not require electrical contacts which are accessible from outside for operation of the device.
  • In order to achieve this object the present invention provides an electronic anti-theft device of the type specified above, the main characteristic of which lies in the fact that the receiver part comprises:
    • - an oscillator,
    • - a resonant circuit connected to the oscillator and including a first inductance,
    • - a detector circuit arranged to output an electrical signal indicative of variations in the voltage characteristics across the first inductance,
    • - a comparator circuit connected to the detector circuit and arranged to output an enabling signal when the sequential combination of the signal output of the detector circuit coincides with a predetermined sequential combination. and in that the electronic key includes:
    • - a second inductance which can be coupled magnetically to the first inductance due to the coupling of the elec--tronic key to the receiver part, and
    • - an electronic control circuit connected to the second inductance and arranged to vary statically the degree of magnetic coupling between the first and second inductances in a predetermined manner when the electronic key is coupled to the receiver part, so as to cause corresponding variations in the characteristics of the voltage across the first inductance.
  • The further characteristics and advantages of the electronic anti-theft device according to the invention will emerge fromthe detailed description which follows, given with reference to the appended drawings, provided purely by way of non-limiting example, in which:
    • Figure 1 is a partially sectioned view of one embodiment of the device according to the invention,
    • Figure 2 is an electrical diagram illustrating the circuits included in the fixed receiver part and in the electronic key of the device according to the invention, and
    • Figure 3 illustrates graphically possible waveform of a voltage signal present in the electronic circuit of the electronic key of the device according to the invention.
  • With reference to Figures 1 and 2, the electronic anti-theft device according to the invention includes an electronic key 1 which can be engaged with a receiver part 2 fixed, for example, to a wall 3 close to a door for access to an environment (not shown).
  • With reference to Figure 2, the receiver part 2 includes an oscillator 4 connected to a resonant circuit of the LC-series type including a capacitor 5 and an inductance 6. 7 shows an amplitude demodulating circuit having its input connected to the common terminal of the inductance 6 and the capacitor 5. The output of the demodulating circuit 7 is connected to a comparator and recognition circuit 8 the output of which is connected to actuator means (not shown) constituted,for example,by devices for opening a lock or devices which control the operation of optical and/or acoustical type alarms.
  • The electronic key 1 includes a second inductance 9 intended to be coupled magnetically to the inductance 6 of the receiver part 2 when the electronic key 1 is engaged with the receiver part. For this purpose, as illustrated by way of example in Figure 1, the receiver part 2 includes a support body 2a having afrontally open recess 2b for receiving a complementary shaped projection 1a which extends from an end face of the electronic key 1. Within the receiver part 2, around the walls which define the recess 2b,is located the winding of the inductance which, in the embodiment illustrated, is constituted by an annular coil. Within the projection 1a of the electronic key 1 is located the winding of the inductance 9 which is also constituted by an annular coil. When the electronic key 1 is engaged with the receiver part 2 the projection 1a of the key engages the recess 2b of this receiver part and the inductance winding 9 is located concentrically within the inductance winding 6. The magnetic field generated by the current circulating in the inductance 6 is, in this situation, coupled to the inductance winding 9 of the electronic key 1.
  • A transistor 10, of the NPN type,has its emitter connected to one end of the inductance winding 9 and its collector connected to the other end of this winding through a resistor 11. This resistor has a rather low resistance value. The point of connection of the inductance winding 9 to the resistor 11 is connected to the anode of a rectifier diode 12, the cathode of which is connected to the input of a stabilized supply 13. A capacitor 14 is connected between the cathode of the diode 12 and earth.
  • AA coded-binary signal generator circuit 15 has its output connecte o the base of the transistor 10 through a resistor 16 and an inverter 15a. The coded-signal generator circuit 15 is arranged to output an information signal of the type illustrated by way of example in Figure 3. This signal includes successive signal portions of equal duration T with each of which is associated an information bit. Each of these signal portions may assume a first or a second waveform according to whether the information bit associated therewith corresponds to a logic "0" or a logic "1". In particular, for reasons which will be clarified below, the waveform associated with "0" is preferably constituted by a pulse of duration T having a constant amplitude V0. The waveform associated with "1" is constituted by a pulse of duration τ<T, having a constant amplitude Vo followed or preceded by an interval of duration T - τ in which the signal has substantially zero anplitude. Figure 3 shows a portion of signal associated with the sequence "....010....".
  • The waveform 3 associated with the "0" and the "1" may obviously be interchanged.
  • On the basis of what has been explained above a characteristic of the coded signal emitted by the generator circuit 15 is clear: the average value in a time interval T of the coded signal emitted by the generator circuit 15 is always different from zero. The importance of this characteristic will be clarified in the description of the operation of the device according to the invention.
  • The oscillator 4 is arranged,in a manner known per se to generate a signal having a predetermined frequency wnich is independent of the variations in the load impedance of the oscillator. Preferably the resonant frequency of the resonant circuit comprising the capacitor 5 and the inductance 6, under the conditions in which the electronic key is not engaged with the receiver part, is the same as the frequency of the oscillator 4. This frequency may for example, be 100 KHz.
  • In the condition in which the electronic key is not engaged with the receiver part, the amplitude of the voltage across the inductance 6 remains constant. Consequently the output signal of the demodulator circuit 7 is a continuous signal, which,under these conditions, has a constant amplitude.
  • It will now be supposed that the receiver part 2 is engaged by an electronic key 1. This engagement establishes magnetic coupling between the inductances 6 and 9 which constitute a transformer. Hence in this situation a voltage is established across the inductance 9 which is rectified by the diode 12 and smoothed by the capacitor 14. The rectified and smoothed voltage is fed to the stabilized supply 13 which provides a continuous stabilized supply voltage to the coded-signal generator circuit 15. This latter circuit, which may comprise, in a manner known per se, memory circuits or shift resisters and their control circuits, provides a coded output signal constituted by a succession of n bit. A portion of this coded signals has been described with reference to Figure 3 by way of example. This coded signal is passed through the inverter 15a to the transistor base 10. Consequently when the coded signal has an amplitude V0 the transistor 10 is cut off. When the coded signal has a substantially zero amplitude the transistor 10 is saturated. At each change from the condition of saturation to the condition of cut-off of the transistor 10 there is a corresponding variation which can be sensed by the inductive component of the impedance of the resonant circuit in the receiver part 2. The resonant frequency of this circuit, and consequently the amplitude of the voltage across the inductance 6 varies correspondingly. In other words, the coded signal emitted by the generator circuit 15 acts as a signal modulating the amplitude of the voltage across the inductance 6. The amplitude demodulator 7 outputs a unidirectional signal the sequential progress of which follows the variations in the sequential progress of the modulating signal, that is, the signal putput of the generator circuit 15. The signal output of the demodulating circuit 7 is compared by the comparator and recognition circuit 8 with a predetermined reference sequence. When these coincide, the .electronic key 1 coupled to the receiver part 2 is "recognised" and the comparator and recognition circuit 8 outputs an enabling signal to actuator means of the type mentioned above, or prevents the actuation of alarm means. In the case of lack of recognition of the key, the comparator and recognition circuit 8 activates the alarm means or inhibits the actuation of the actuator means mentioned above.
  • When the signal output of the generator circuit 15 causes saturation of the transistor 10 the inductance 9 is substantially short-circuited. In this situation it is necessary that the short-circuiting of the inductance 9 does not last for an excessively long time, in order to avoid reduction of the supply of the coded-signal generator circuit 15. For this purpose the coded signal ouput of the generator circuit 15 must not remain at the low level beyond a fraction of the duration T of an individual portion of the coded signal. The above-mentioned characteristic of the coded signal output of the generator circuit 15 lies in the fact that this coded signal has an average v lue which is not zero in any time interval of duration T, ensuring the continuity of the supply to the coded signal generator circuit 15 when the key 1 is inserted in the receiver part 2.
  • When the electronic key 1 is removed from the receiver part of the signal output of the demodulator circuit 7 again takes on a constant amplitude equal to that present before the insertion of the key, while the coded signal generator circuit 15 within the key, after a certain delay related to the discharge time constant of the capacitor 14, stops operating.
  • The electronic key anti-theft device according to the present invention has the advantage of not requiring the use of fixed contacts for the key and the receiver part and thus is free of all the disadvantges which result from the presence of such contacts.

Claims (8)

1. Electronic anti-theft device including an electronic key (1) which can be engaged with a fixed receiver part (2) having the function of carrying out a process of identification of the electronic key (1) engaged therewith, and of providing an enabling signal to actuator means when the electronic key (1)engaged with the receiver part (2) has predetermined characteristics, characterised in that the receiver part (2) includes:
- an oscillator (4),
- a resonant circuit (5, 6) connected to the oscillator (4) and including a first inductance (6),
- a detector circuit (7) arranged to output an electrical signal indicative of variations in the voltage characteristics across the first inductance (6),
- a comparator circuit (8) connected to the detector circuit (7) and arranged to output an enabling signal when the signal output of the detector circuit (7) coincides with a predetermined signal, and in that the electronic key (1) includes:
- a second inductance (9) which can be coupled magnetically to the first inductance (6) due to the engagement of the electronic key (1) with the receiver part (2), and
- an electronic control circuit (10-16) connected to the second inductance (9) and arranged to vary statically the degree of magnetic coupling between the first and second inductances (6, 9) according to a predetermined manner when the electronic key (1) is engaged with the receiver part (2), so as to cause corresponding variations in the characteristics of the voltage across the first inductance (6).
2. Device according to Claim 1, characterised in that the oscillator (4) is arranged to supply the resonant circuit (5, 6) with a signal having a frequency which is substantially constant and independent of the load impedance of the oscillator (4),
and in that the electronic control circuit (10-16) is arranged to modify the magnetic coupling between the first and second inductances (6, 9) so as to vary the resonant frequency of the resonant circuit (5, 6) and modulate the amplitude of the voltage across the first inductance (6).
3. Device according to Claim 2, characterised in that the resonant circuit (5, 6) has a resonant frequency substantially the same as the frequency of the oscillator (4) when no electronic key (1) is engaged with the receiver part (2).
4. Device according to Claim 2 or 3, characterised in that the detector circuit includes an amplitude demodualtor circuit (7).
5. Device according to any one of claims 1 to 4, characterised in that the electronic control circuit includes a transistor (10) with its collector-emitter path connected in parallel to the second inductance (9) and its base connected to the output of a circuit (15) for generating coded binary signals.
6. Device according to Claim 5, in which the circuit (15) for generating coded binary signals is arranged to output a signal comprising successive signal portions of the same duration (T) with each of which is associated an information bit, each of the signal portions assuming a first or a second waveform according to whether the information bit associated therewith corresponds to a logic "O" or a logic "1",charactersed in that the first waveform is constituted by a voltage signal of constant amplitude V0 and is not zero,
and in that the second waveform is constituted by a voltage signal of constant amplitude V0 which is not zero and by a complementary signal portion of voltage of substantially zero amplitude.
7. Device according to Claim 6, characterised in that the electronic control circuit further includes a supply circuit (12-14) connected to the second inductance (9) and to the circuit (15) for generating coded binary signals; the. supply circuit (12-14) being arranged to provide a supply voltage to the circuit (15) for generating coded binary signals due to the magnetic coupling between the first and the second inductances (6, 9).
8. Device according to Claim 7, characterised in that the supply circuit (12-14) includes a rectifier diode (12) connected to the second inductance (9), a smoothing capacitor (14) connected to the rectifier diode (12) and to the second inductance (9), and a stabilized supply (12) connected to the capacitor (14).
EP83830002A 1983-01-11 1983-01-11 Electronic antitheft device comprising an electronic key Withdrawn EP0115747A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP83830002A EP0115747A1 (en) 1983-01-11 1983-01-11 Electronic antitheft device comprising an electronic key

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP83830002A EP0115747A1 (en) 1983-01-11 1983-01-11 Electronic antitheft device comprising an electronic key

Publications (1)

Publication Number Publication Date
EP0115747A1 true EP0115747A1 (en) 1984-08-15

Family

ID=8191588

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83830002A Withdrawn EP0115747A1 (en) 1983-01-11 1983-01-11 Electronic antitheft device comprising an electronic key

Country Status (1)

Country Link
EP (1) EP0115747A1 (en)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2158870A (en) * 1984-05-17 1985-11-20 Waertsilae Oy Ab Locking system
GB2174452A (en) * 1985-05-03 1986-11-05 Ymos Ag A locking device operating by mechanical and electrical means
US4663952A (en) * 1985-01-18 1987-05-12 Egon Gelhard Device for the contactless coupling of the control and output currents between the electronic elements on the locking cylinder and the electronic elements in the key of an electro/mechanical locking device
FR2603933A1 (en) * 1986-09-17 1988-03-18 Espinadel Gerard Device for control by proximity, in particular of electrical locks
WO1988003594A1 (en) * 1986-11-14 1988-05-19 Nederlandse Organisatie Voor Toegepast-Natuurweten Identification system
FR2619410A2 (en) * 1986-09-17 1989-02-17 Espinadel Gerard Proximity control device in particular for electric locks
GB2209793A (en) * 1985-11-21 1989-05-24 Kokusan Kinzoku Kogyo Kk Wireless signal controlled vehicle lock system
EP0514772A1 (en) * 1991-05-22 1992-11-25 Kabushiki Kaisha TEC Key device
EP0640734A1 (en) * 1993-08-31 1995-03-01 Siemens Aktiengesellschaft Contactless data and/or power transmission system
EP0659963A1 (en) * 1993-12-20 1995-06-28 Siemens Aktiengesellschaft Electronic immobilizing device for a motor vehicle
FR2721882A1 (en) * 1994-07-04 1996-01-05 Valeo Securite Habitacle Key detector for vehicle anti-theft system
FR2731035A1 (en) * 1995-02-28 1996-08-30 Ymos France ASSEMBLY CONSISTING OF AN ELECTRIC DOOR LOCK WITH ELECTRIC EMERGENCY FUNCTION AND ITS CONTROL MEANS, AND EQUIPMENT CONSISTING OF SEVERAL OF THESE ASSEMBLIES
EP0730071A1 (en) * 1995-03-03 1996-09-04 Siemens Aktiengesellschaft Anti-theft system for a motor vehicle
EP0767286A2 (en) * 1995-10-02 1997-04-09 Motorola, Inc. Remote keyless entry and immobilization system for automotive use
WO1997030255A1 (en) * 1996-02-15 1997-08-21 Toyota Jidosha Kabushiki Kaisha Locking system for a vehicle
DE19729402A1 (en) * 1997-07-09 1999-02-11 Siemens Ag Motor vehicle anti-theft protection system
DE19748329A1 (en) * 1997-10-31 1999-05-06 Siemens Ag Device for identifying key inserted into motor vehicle injection lock
DE4341333B4 (en) * 1993-12-03 2004-04-29 Deltron Elektronische Systeme Gmbh Method for operating an electronic immobilizer and electronic immobilizer for motor vehicles
DE4434587B4 (en) * 1993-10-01 2004-12-16 Marquardt Gmbh Electronic ignition lock system on a motor vehicle
CN101189405B (en) * 2005-05-31 2012-02-01 三洋电机株式会社 Electronic key system and autobicycle using the same
US8122746B2 (en) 1995-09-29 2012-02-28 Hyatt Jr Richard G Electromechanical cylinder plug
US8528373B2 (en) 1997-06-06 2013-09-10 Richard G. Hyatt, Jr. Electronic cam assembly
EP2266123B1 (en) 2008-03-17 2018-10-10 Powermat Technologies Ltd. Inductive transmission system
US11387688B2 (en) 2008-07-02 2022-07-12 Powermat Technologies, Ltd. System and method for coded communication signals regulating inductive power transmissions

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3979647A (en) * 1975-06-11 1976-09-07 The Eastern Company Inductively coupled lock
DE2634303A1 (en) * 1976-07-30 1978-02-02 Knorr Bremse Gmbh Electronic lock and key system - uses contactless data exchange and compares generated and stored signals
GB1531951A (en) * 1977-02-04 1978-11-15 Eastern Co Keyhole-less electronic lock

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3979647A (en) * 1975-06-11 1976-09-07 The Eastern Company Inductively coupled lock
DE2634303A1 (en) * 1976-07-30 1978-02-02 Knorr Bremse Gmbh Electronic lock and key system - uses contactless data exchange and compares generated and stored signals
GB1531951A (en) * 1977-02-04 1978-11-15 Eastern Co Keyhole-less electronic lock

Cited By (36)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2158870A (en) * 1984-05-17 1985-11-20 Waertsilae Oy Ab Locking system
US4663952A (en) * 1985-01-18 1987-05-12 Egon Gelhard Device for the contactless coupling of the control and output currents between the electronic elements on the locking cylinder and the electronic elements in the key of an electro/mechanical locking device
GB2174452A (en) * 1985-05-03 1986-11-05 Ymos Ag A locking device operating by mechanical and electrical means
GB2209793A (en) * 1985-11-21 1989-05-24 Kokusan Kinzoku Kogyo Kk Wireless signal controlled vehicle lock system
GB2209793B (en) * 1985-11-21 1990-12-19 Kokusan Kinzoku Kogyo Kk Wireless signal controlled vehicle lock system
FR2603933A1 (en) * 1986-09-17 1988-03-18 Espinadel Gerard Device for control by proximity, in particular of electrical locks
FR2619410A2 (en) * 1986-09-17 1989-02-17 Espinadel Gerard Proximity control device in particular for electric locks
WO1988003594A1 (en) * 1986-11-14 1988-05-19 Nederlandse Organisatie Voor Toegepast-Natuurweten Identification system
EP0514772A1 (en) * 1991-05-22 1992-11-25 Kabushiki Kaisha TEC Key device
US5268560A (en) * 1991-05-22 1993-12-07 Tokyo Electric Co., Ltd. Key device
EP0640734A1 (en) * 1993-08-31 1995-03-01 Siemens Aktiengesellschaft Contactless data and/or power transmission system
DE4434587B4 (en) * 1993-10-01 2004-12-16 Marquardt Gmbh Electronic ignition lock system on a motor vehicle
DE4341333B4 (en) * 1993-12-03 2004-04-29 Deltron Elektronische Systeme Gmbh Method for operating an electronic immobilizer and electronic immobilizer for motor vehicles
EP0659963A1 (en) * 1993-12-20 1995-06-28 Siemens Aktiengesellschaft Electronic immobilizing device for a motor vehicle
FR2721882A1 (en) * 1994-07-04 1996-01-05 Valeo Securite Habitacle Key detector for vehicle anti-theft system
EP0730072A1 (en) * 1995-02-28 1996-09-04 Ymos France Arrangement comprising an electric door lock with an electrical emergency function and its control means
FR2731035A1 (en) * 1995-02-28 1996-08-30 Ymos France ASSEMBLY CONSISTING OF AN ELECTRIC DOOR LOCK WITH ELECTRIC EMERGENCY FUNCTION AND ITS CONTROL MEANS, AND EQUIPMENT CONSISTING OF SEVERAL OF THESE ASSEMBLIES
EP0730071A1 (en) * 1995-03-03 1996-09-04 Siemens Aktiengesellschaft Anti-theft system for a motor vehicle
US5889471A (en) * 1995-03-03 1999-03-30 Siemens Aktiengesellschaft Anti-theft system for a motor vehicle
US8141399B2 (en) 1995-09-29 2012-03-27 Hyatt Jr Richard G Electromechanical cylinder plug
US8122746B2 (en) 1995-09-29 2012-02-28 Hyatt Jr Richard G Electromechanical cylinder plug
EP0767286A3 (en) * 1995-10-02 1998-10-14 Motorola, Inc. Remote keyless entry and immobilization system for automotive use
EP0767286A2 (en) * 1995-10-02 1997-04-09 Motorola, Inc. Remote keyless entry and immobilization system for automotive use
WO1997030255A1 (en) * 1996-02-15 1997-08-21 Toyota Jidosha Kabushiki Kaisha Locking system for a vehicle
US8528373B2 (en) 1997-06-06 2013-09-10 Richard G. Hyatt, Jr. Electronic cam assembly
DE19729402A1 (en) * 1997-07-09 1999-02-11 Siemens Ag Motor vehicle anti-theft protection system
DE19729402C2 (en) * 1997-07-09 2003-07-03 Siemens Ag Anti-theft system for a motor vehicle
US6351206B1 (en) 1997-07-09 2002-02-26 Siemens Aktiengesellschaft Antitheft protection system for a motor vehicle
DE19748329A1 (en) * 1997-10-31 1999-05-06 Siemens Ag Device for identifying key inserted into motor vehicle injection lock
FR2770563A1 (en) 1997-10-31 1999-05-07 Siemens Ag DEVICE FOR RECOGNIZING A KEY ENGAGED IN A MOTOR VEHICLE LOCK
US6396390B1 (en) 1997-10-31 2002-05-28 Siemens Aktiengesellschaft Device for detecting a key inserted into a motor vehicle lock
DE19748329C2 (en) * 1997-10-31 1999-12-30 Siemens Ag Device for recognizing a key inserted into a motor vehicle lock
CN101189405B (en) * 2005-05-31 2012-02-01 三洋电机株式会社 Electronic key system and autobicycle using the same
EP2266123B1 (en) 2008-03-17 2018-10-10 Powermat Technologies Ltd. Inductive transmission system
US11837399B2 (en) 2008-03-17 2023-12-05 Powermat Technologies, Ltd. Transmission-guard system and method for an inductive power supply
US11387688B2 (en) 2008-07-02 2022-07-12 Powermat Technologies, Ltd. System and method for coded communication signals regulating inductive power transmissions

Similar Documents

Publication Publication Date Title
EP0115747A1 (en) Electronic antitheft device comprising an electronic key
US5469098A (en) Isolated gate drive
US4567511A (en) Transmitting and storing data relating to television viewing
US4864292A (en) Identification system
WO1996015590A1 (en) Electrical circuit utilizing avalanche transistor for generating and transmitting sine-wave energy pulses
EP1047947B1 (en) Test device for testing a module for a data carrier intended for contactless communication
GB2098431A (en) Apparatus for the contactless transmission of a numerical value
US3754187A (en) Transmitter-receiver system
US5376932A (en) System for exchanging information between a portable object such as a key and an exchange device
US4672686A (en) High frequency antenna tuning device
US3958105A (en) Electronic recognition and identification system for identifying several master keys
US3400219A (en) Remote station apparatus for remote control system via telephone line
US4376269A (en) Electronic security memory including on-off controlled oscillator
EP0360160B1 (en) Logic signal circuit for a releasing relay
GB2143354A (en) Storing data relating to television viewing
EP1393245B1 (en) Communication between a transponder and an interrogator
US3675109A (en) Information transmitting device
US3975647A (en) Bootstrap circuit
IT8946889A1 (en) AUTOMATIC SELECTION CIRCUIT FOR AUDIO TELEVISION SYSTEMS_MULT TI-SYSTEMATIC
US3898582A (en) Transmitter encoder with output for a time period
US4833703A (en) On-hook control circuit for answering machine
JPH025336B2 (en)
JPS6260032B2 (en)
JPS61186050A (en) Evaluation circuit for alterating current or ac voltage
GB2140947A (en) Transmitting and storing data relating to television viewing

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): AT BE CH DE FR GB IT LI NL SE

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: SAET S.P.A.

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19850416

RIN1 Information on inventor provided before grant (corrected)

Inventor name: CROSETTO, PIETRO